1988 年 67 巻 12 号 p. 1061-1069
The reaction rates of 32 coal chars with steam (1173-1273 K, 9. 8-37 kPa) and 11 coal chars with carbon dioxide (1223-1273 K, 16-37 kPa) were measured in a thermobalance. Coals ranging from anthracite to brown coal were used. The effects of partial pressures of steam and carbon dioxide, reaction temperature, characteristic properties of coal on the gasification rate were in-vestigated. The following empirical equations to estimate the gasification rate of coal char were ob-tained. The gasification rates estimated by these equations were in fair agreement with the experimen-tal ones.
Steam gasification
r0.5=96· ((Ca+Na) · (O/C)) 0.30·exp (-170×103/RT) ·PH2O0.70
CO2 gasification
r0.5 =7380· (Ca+Na), 0.92·exp (-215×103/RT) ·PCO20.67
where
Ca: Ca content in char (mmol/g-char)
Na: Na content in char (mmol/g-char)
O: Oxygen content in coal (%, daf)
C: Carbon content in coal (%, daf)
T: Temperature (K)
P: Partial pressure of reactant gas (Pa)